I have a hum-related thread going on the SE84C+ forum, and I've noticed a few similar threads on other forums.

However, in the bigger picture of general hum/noise reduction, I'm just curious if anyone else has employed solutions like isolation transformers, power regenerators (like the PS Audio Power Plant Premier), line conditioners, and the like -- and what your results have been.

And I'm particularly interested in any good bang-for-the-buck solutions.

In fact, I noticed that Steve even mentions the PS Audio unit in his discussion of why the Mini Torii's tube regulation is so useful (on the Mini Torii's web page).

Anyway, any thoughts or suggestions?

Mark Blairrelatively new SE84C+ owner (with just a slight bit of noticeable hum)

I get to try out a PS Audio Power Plant Premier tonight! I'll post impressions afterward.

I've always had a slight hum issue with my Zen kit that I've deductively traced to the power transformer. It'll be interesting to see if balanced power has a positive effect.

I see that PS Audio has a new line of power generators. They are calling them perfect wave. They note that output impedance is improved, which implies that the Premier's output impedance was higher than desired. My novice impression is that a high output impedance would slow it's ability to provide current quickly on demand. Perhaps not such an issue if the device it is powering has a proper power supply.

Removing all the marketing fluff, these power generators are essentially an amplifier reproducing a 60hz sine wave. Obviously the load of the power supplies will vary drastically and so the question is can it be designed to drive all these different types of loads optimally. My guess is probably not.

I've wondered how much a high current isolation transformer (converting single ended power to balanced) would help by comparison. It may be that much of the benefit that a power generator offers can be accomplished with this much simpler device.

Very curious to find out if the PS Audio Power Plant Premier makes a significant difference.

And I'm probably not inclined to build my own isolation transformer at this time (which probably explains why I purchased the SE84C+ instead of getting the kit) -- but I'd sure like to know whether it could address my specific hum situation (as described in my thread under the SE84C+ forum).

I have not tried one, but bet it is good because I believe I recall hearing about them from some respectable Decware types....the TrippLite isolation transformer. They make two 500 watt units...the IS500 and the IS500HG, HG being Hospital Grade. I have been tempted by the the HG because it is built better with good outlets. The HG retails over 300, but I saw it for as little as 225 online.

Even though my minor hum is not in the way to me (only slightly audible at reasonable volume settings and without music coming through the speakers) I'm wondering what another level of cleanliness with power might do. Everything I have done to refine the power has done much more than work on Hum, refining every detail.

Since you have been reading about the PS Audio rigs, it might be interesting to compare what the TrippLite does. If similar, and the store will allow refunds, the price is a no-brainer.

Well the Power Premier is certainly a positive influence. Can't find anything wrong with it's effect on the music. Everything it does is for the better. Hum is still there if you listen for it.

I've plugged in my USB to digital audio re-clocker, DAC, and Select. It's fun to think about each piece of gear in the system benefiting from cleaner sine waves.

Naturally a typical piece of audio gear has to have a built in AC to DC converter (Power Supply) so as to be plug and play.

It's an interesting situation where adding this power generator yields a process of converting home AC power to DC to then create new AC power for your gear which then coverts AC back to DC. So even with this added complexity the end result is cleaner.

Thinking about your system in this way leads to concepts of running an all DC system powered off of battery banks stored in the garage to eliminate this AC problem altogether. How cool would it be to have a system where the only existent AC signal was the music?

Here goes trying to explain what I'm hearing...

First thing I noticed is that the music sounds much more hearty and weighted. The bottom end much more present and articulate. this with the added clarity leads one to crank it up and when I did it was surprising how much more volume I could use without it getting brash.

I'm going out on a limb to try and describe the effect it's had on the tone. It feels like the vibrations in the room are gripping more definitely and I can feel myself vibrating. So in other words I can feel the music even in the middle frequencies rather than just hearing it.

Thinking of the music as the super complex air ripples that they are, there is a sense that the peaks and dips of the ripples are sharper and cleaner which in effect has a better hold over the room. Another way to put it is that the system has more speed which has yielded cleaner sonic tones and sense of pressure that is realistic in scale.

It just sounds amazing.

It's interesting to note that the unit has meters for incoming voltage and THD, as well as output.

Last night my house power was running at 120v. This morning it is reading 123v and 2% THD.

Years ago I home auditioned one of the original PS Audio units and even owned battery powered Tripath and DAC at two vastly different residental wiring/power situations. None made any difference.

But power abberations (that's the technically correct term) are a localized phenom. In fact the most dramatic experience I've ever heard was at the first Decfest that Steve hosted. He's in what might be described as an older light industrial neighborhood and after 11 PM, the sound cleaned up quite noticeably.

Power, AC and DC have been a fascination for me for decades. I too, have owned numerous power conditioners including PS Audio, Tripplite, Brickwall, and BPT. I've owned them all in separate homes and AC situations. Each has some benefits, but also limitations. But as far as addressing hum problems, n one have had much, if any effect. Using a DC/battery preamp was the best solution that I ever tried. As mentioned before, hum is a local problem associated to a single unit. So many times, it has been a power amp. I know this by disconnecting the input and just turning it on and listening to the hum from the amp. I wish I had some easy suggestions, but usually, I have just replaced the amp. The only other experiment is to remove the earth ground, but I know you have already tried those things...good luck.... :-/

I came across this thread after noticing in the Mini Torii manual that Steve states:

Quote:

It makes little sense to invest too much in a power cord if your going to plug itdirectly into the wall outlet because far more of a problem than the cord itselfis the dirty power coming from the outlet. What does make sense is to purchase asimple isolation transformer rated for 500 Watts or so and use that to decoupleyourself from the grid and all the nasty harmonics that float in it. Then take agood power cord plugged into the isolation transformer and you will have a result.

Right now, I have my office headphone setup on a Monster AVS-2000 and HTS5100 MkII. An office is an electrically noisy place, and so am wondering if I might gain some benefit to add an isolation transformer in here. I have exceptionally low hum on my Taboo, and when listening to music, I cannot hear it. But with no signal, my amp is not "dead black."

I found some good prices on Tripp Lite 500W and 1000W units at Amazon, and so it would be a low risk affair to try them out. All totaled, my equipment falls well under 500W, but is there some rule of thumb on how much "spare room" is enough?

Pale Rider. This makes sense to me. And 4krow, your comments also make sense to me. If you have a ground problem in the amp, good power will help the sound but not fix the hum. Though it can be totally the amp, hum is not always totally, or even partially the amp. It can be the amp's interaction with ground issues with other components, power cables, interconnects, cable layout, or leaked over noise from other appliances, rheostats, computers etc in the circuit or leg of the circuit board, bad receptacles, loose ground connections....or from transformers before your house....lots of stuff can contribute even if you isolate the primary offender as the amp.

Everything I have done to refine the power coming in...hospital grade plug, Alan Maher filters, Brickhouse...have helped lower the hum a bit while improving the "Black" and this is why i have been looking into this subject....not because my hum is intimidating, but because any hum is interfering with the sound.

Lets not forget that an isolation transformer in and of itself only isolates from hash and the effects of some noise. It is important that the output of the transformer is balanced, thereby canceling the common mode noise. Hum as such, is not going to be affected. Only noise that resides on both sides of the line will be put out of phase with itself, producing a null of that noise. The BPT website might help shed some light on this problem as well as the PS Audio site, especially in forums.

Changing the voltage from 0 to 60v with each leg of the power should cause no trouble with your equipment. I will say however, that I once owned a PS Audio 300, and used it to power a Krell cd player. I can't say what happened, but the cd player quit working immediately! Was it the power supply? I'll never know. Having said that, I have used countless pieces of equipment using balanced power with no other problems. I have owned 3 different Tripplite products over the years and have not had any significant problems with hum. Remember, the Tripplite product adjusts the voltage using different secondary taps on the transformer, but does not supply balanced power. And I'm not so sure that the quality of the components inside are really up to the standards of other power equipment. I looked at the link 'Transcendent Sound' and the products do look promising. Again, I do not know if the transformers have the same quality as BPT or some of the other brands out there. Also, that unit is able to supply 8 amps. of current. That would be enough for some systems, but it is always wise to add up the total current needs of your system. Lastly, I might recommend a BPT product that I currently own only because of one unique feature. The primary winding of this transformer is rated at 10 amps of continuous current, but it has 8 SEPARATE secondary windings that are also rated at 10 amps each. What this means is that each winding is like having a dedicated circuit that does not interact with the other windings. Pretty cool idea, I think. That means you can totally separate digital from analog, preamp from power amp, etc.

Seank, I haven't done a kit in a while, but your link to the Transcendent came in just in time to keep me from ordering the Tripp Lite. I may still try the TL, since I can send it back, but I am definitely going to try the Transcendent. I am also investigating 4krow's BPT.

Like Will, I don't have a hum "problem." I am just looking for better clarity, blacker black.

And Brett, did you decide to keep the PS Audio Power Plant Premier? Partially because of your comments, I decided to purchase a used one from eBay.

But I'm pretty sure it won't address what seems to be my SE84C+'s very small amount of hum (barely audible at near field listening distances with no music playing) -- so I'm still confused about what's the best bang-for-the-buck way to deal with that.

I like JLM's comments regarding the quality of power varying from area to area. I'm pretty sure the quality of my power here is much worse than my last home. Since living here my stereo just hasn't been as enjoyable. Adding the power plant has made a night and day difference and I've been reminded why I love this hobby so much. After many days of listening it's still an obvious improvement. My buddy will be asking to have this back pretty soon unfortunately so I'll probably wind up getting one for myself.

I think it did reduce the hum a bit. As others have commented, it will depend on the source of the hum rather having balanced power has an effect. I listen at near field as well, but as I've said elsewhere I've heard a few zen amps and normally they are DEAD quiet. Mine has an issue with the power transformer and it's possible there could be a similar issue with your amp.

I guess there's no getting around this -- I'm probably going to have to buy a voltmeter that can measure whether the amp is within specs (1.5mV hum max) or not. And if so, since I just purchased it, it should be covered under the lifetime warranty. I'd just hate to be without it for the time that would be required so send it in and get it repaired.

I just wish I could think of a brilliant way to use my SPL meter to calculate what the noise level is based upon the noise level SPL. So -- if anybody has any brilliant ideas on how do do this, I'm all ears!

Volt meters are dirt cheap now, but unless you know you have totally clean power, good ground, cable and all, and if it is over 1.5 mV, I wonder how you can tell if it is the amp or the power, or a combination?

And I know what you mean about not wanting to send your beloved gear in for repair. Have you called Steve? He has been troubleshooting over the phone for years and knows these amps like no one else!

Good point, Will -- so I'll probably wait until my PS Audio Power Plant Premier arrives so I can see if/how it affects the hum.

Though I've posted details in the separate SE84C+ forum, the big picture is that at near field distances (about 30" away) with 90dB PMC TB2S+ speakers, no inputs connected, anp volume at max, only speakers connected, I can just barely hear a bit of hum (no audio, of course, since no inputs are connected), and the hum doesn't vary with the amp's volume knob setting.

Also, I've e-mailed Steve a copule of times, but I've gotten no response (an no response from the SE84C+ forum posting, either).

So in a few weeks (after getting my power pristine), I'll probably take your advice and try to give Steve a call about the hum issue.

Yes I get it. Sounds like pretty minor hum. Why not test it? If it is under 1.5 mV, you know it is at least acceptable to Steve. Seems like these things are so transparent that minor transformer hum could be easily excited and then very easily heard.

Hope you get more good insights!

And I can tell you that in my experience, Steve is a phone guy if you really want to get up with him. Seems he gets way too many emails to keep up.

Mark, it seems that this is a hum that you strain to hear from the listening position with no music playing, maybe not even hear it from your listening position? I've had those come and go in my system, and I just go "okay" and get into the music and I'm not bothered. I'd recommend that approach if possible.

If you've gone through Steve's paper on hum, the next step is really just to call him up on the phone. No one knows more about these amps than he does. And he can steer you to "what it is."

FWIW, my Transcendent Balanced Power Supply kit arrived yesterday. It is an impressive, nicely done kit, with excellent step-by-step color instructions. Does not look difficult at all. Going to tackle it this weekend.

Lon - Sorry about the late reply. Good advice! I still need to get my act together and get a voltmeter that reads AC voltage that low. But I read Steve's paper on hum troubleshooting, and it too seems to confirm that it's an issue with the amp. But it comes down to needing to simply do the measurement to see whether it's out of spec of not.

Regardless, I really like the SE84C+ amp! Even more so since I've added the PS Audio Power Plant Premier to my setup. And I've just gotten the notice that the Decware speaker cables and interconnect that I ordered recently were just shipped -- so hopefully the sound will improve even more.

And Pale Rider, I'd love to know what effect your balanced power supply has on the sound...

Glad the Premier has been a beneficial addition. I think you'll really like the interconnects. I can't be without them now myself, any other interconnect just doesn't sound 100 percent right. And the speaker cables. . . well they take a very long time, a very long time to burn in completely or at least my pair does. They sound great, but bass shy for some time. But they are without exception the best speaker cables I've ever used and I just love their sound. . . or lack of sound.

To be honest the speaker wires sounded as if they were breaking in for over a month in my system, and took even longer to fully flesh out the lower frequencies. That said, they still sounded magnificent as they were breaking in, better than any other cables I've owned, with the sweetest treble I'd ever had, so I was not unhappy to be listening to them break in, was just wondering and hoping the bass would come in and they did. These are the items that took the longest to break in of any that I've ever used. If you look in the thread about them on this forum you'll see my experience chronicled.

The interconnects have a similar break in cycle, but shorter. I think within two weeks they're fully operational and just get better slowly over time. There's a poster here who couldn't bear the sound of them raw and began to like them after a month or two of use in another system. That doesn't exactly match my experience, but they do season well over time.

The other thing to consider is there's no place to hide with these cables if you are feeding them mediocre sound. They're going to show you what you've got.

I have a Tripplite iso transformer and am wondering if I shoult fit it with a thick gauge power cord instead of the rather thin one it was born with.

Raduschka, I gotta believe that improving the wiring into that box will be a good thing. If you read Steve's piece about power cords, the thinking of "the more you can do to get your connections 'out of the way,' the better off your sound will be" makes sense. Not sure why TrippLie would go to the trouble of building an iso transformer while fitting it with a crummy cord, though the old free market driver of cutting costs comes to mind. ;) anyway, is it hard-wired? I am still considering a Tipp Lite. Experiences reported here are mixed, but Steve has recommended them. Which model do you have?

I just finished correcting a builder's error in my Transcendent balanced power supply, and am looking forward to getting my Taboo plugged into it.

hmm,I think I can say I have mixed results with the tripplite, that is why I want to replace its power cable. I find it makes things sound opaque and raspy, compared to a banal monster power conditioner that I also have around the house. The Monster Power makes a huge difference in cleaning the sound and improving the soundstage, probably in a not so subtle way, but I have no point of comparison other than the bare mains, which themselves are not exactly clean here where I live. I have the 250 watt, 2.6 amperes model (from amazon, 99$ I think, quite heavy). I am looking fwd to buying an audiophile grade power conditioner, I have heard a few interesting names here on the forum.I wish I could answer your question, but I do not understand what 'hard-wired' means in this context. I know how it is used in neuro biology I am wondering if it is worth the trouble and if so then which one I should recable, the Tripp or the Monster....

...the monster power conditioner comes with a thicker power cord, although not as thick as some of mine. I also built a power cord with vh audio cryo cables, flavour 4 or something like that, I cannot remember. I think I will order some more of that relatively inexpensive high quality copper cable and rewire everything, my brain if only I could, and report back to youroger and out

I use two Tripplite isolation transformers, one for digital components, one for analog, and they have "captive" (hard-wired: this means they don't use a detachable IEC connector, but are wired directly into the component) cable of sufficient width in my opinion. It's not like they are zipcord.

I really enjoy the sound from the isolation transformer. I used a PS Audio Power Plant for years and did not repair it when it broke down. I find that using these Tripplites, the model that Steve recommends, and using a PS Audio "Duet" power outlet from each, works nearly as well or as well.

Just be sure your Tripplite is not meant for computer use; I've learned that those degrade audio sound.

I'm not sure if they can be made for use with 220v, but I would look into the PS Audio "Duet" . . . they work very well for me.

Good info Raduschka and Lon. I am looking at one of these two TrippLites in concert with, or to compare with, my Transcendent Balanced Power Supply. Anyone know what real difference is between standard and hospital-grade TrippLites?

after some research that convinced me that in theory there is no improvement in the sound from using hospital grade connectors. I have no direct experience, so I cannot give you my hands-on opinion on that, except to say that I have read discussions among audiophiles (that must be what we are) and some seemed to say that aside from the better physical contact, with all its advantages, there is little or no improvement soundwise. It would also make sense. Steve does recommend the hospital grade iso transformer in one of his papers though.He reassured me per email that the current draw of my Mini Torii and cd player would not exceed its output in terms of amperage (the wattage is 250, with the Mini t consuming 75 at max output)I totally dislike the sound when I plug my system into the tripp lite alone. It is undetailed and recessed, no sparkle, no passion.

I plug both cd player and Minitorii into a 400$ Monster Power conditioner with 2 separate iso filters for analog and digital and everything is restored!

The tripp lite does come with a rather thin power cord. I fitted it with an iec connector and a thick gauge power cord and I noticed a difference in the bottom end.

I tend to think that I am using cheap low quality conditioning components with a high quality system, but who knows if those expensive power conditioners really are that much better. I don't.

I think this fits here, on the topic of power conditioning:...I installed a hospital grade outlet in my living room, as the one I was using was remarkably loose. upon inspection, the wires coming out of the wall were completely darkened by decades of unattended existence so I brought their coppery shine back with a piece of sand paper. Yes, now I have even better sound coming out of my system, easily audible in the bass zone, but the whole sound is more lifelike. Sting-dream of the Blue Turtles MSFL happened to be the cd in the player. Moon over Bourbon street-well, he is right there, on top of the bass and there is a saxophone in the back. "Consider me Gone"-the two notes on the bass, they feel like a real bass guitar being played now and the percussion is life like. etc etcI bought a red leviton hospital grade outlet from frwoodworking on Ebay, for 7$ + 2$ shipping or so. Not the best, but it works for now. http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&item=230625178913&ssPageName=STRK:M...

I put one of those same receptacles in my room that cost I think 14 at Lowes, and I had similar experience. I cleaned up the wires, though they weren't as bad as yours sound, and installing the hospital grade receptacle made a very notable difference. More definition and focus all round.